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Case study: Accessible entrance
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© Commonwealth of Australia and States and Territories of Australia 2021, published by the Australian Building Codes Board.
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© Commonwealth of Australia and States and Territories 2021, published by the Australian Building Codes Board.
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The Australian Building Codes Board, the Commonwealth of Australia and States and Territories of Australia do not accept any liability, including liability for negligence, for any loss (howsoever caused), damage, injury, expense or cost incurred by any person as a result of accessing, using or relying upon this publication, to the maximum extent permitted by law. No representation or warranty is made or given as to the currency, accuracy, reliability, merchantability, fitness for any purpose or completeness of this publication or any information which may appear on any linked websites, or in other linked information sources, and all such representations and warranties are excluded to the extent permitted by law.
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Version history
Original
Publish date: May 2021 Print version: 1.0
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Case study: Accessible entrance
Contents
Purpose and limitations............................................................................................3
Introduction................................................................................................................4
The Design ..................................................................................................................4
The Process ...............................................................................................................5
Step 1 Prepare a performance-based design brief ......................................................5
Step 2 Carry out analysis...........................................................................................18
Step 3 Evaluate results ..............................................................................................19
Step 4 Prepare a final report......................................................................................19
References ...............................................................................................................23
REMINDER
This case study is not mandatory or regulatory in nature and compliance with it will
not necessarily discharge a user's legal obligations. The case study should only be
read and used subject to, and in conjunction with, the general disclaimer at page i.
The case study should be read in conjunction with the relevant legislation of the
appropriate state or territory. It is not intended that the case study will counteract or
conflict with the legislative requirements, any references in legal documents, or
other documents issued by the Administration or any directives by the appropriate
authority.
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Case study: Accessible entrance
Purpose and limitations
This case study has been prepared to accompany the Australian Building Codes
Board (ABCB) Performance Solution Process Handbook, and illustrate the intent and
application of the process (see A2.2(4) of the National Construction Code (NCC)). It
aims to demonstrate a practical application of the NCC Performance Solution
process. Clause A2.2(4) describes the process for developing Performance
Solutions:
1. Prepare a brief
2. Carry out analysis
3. Evaluate results
4. Prepare a final report.
The Performance Solution process handbook explains the steps in the process. The
process is also summarised in the ABCB Guidance Document – Performance
Solution Process, both available from the ABCB website (abcb.gov.au).
This case study assists NCC users in understanding and developing Performance
Solutions. It will be of interest to all parties who are involved in selecting or assessing
elements of buildings that must comply with the NCC.
The guidance in this case study is limited to the Performance Solution process
(A2.2(4)), using an accessibility issue to explore this provision. While a realistic
scenario has been attempted to be recreated in this case study, the technical content
within is purely demonstrative for the purposes of explaining how to use the
Performance Solution process within the NCC and therefore does not demonstrate
full NCC compliance with the NCC Performance Requirements.
Users of this case study are encouraged to check for any State and Territory NCC
Variations and Additions that may apply in their jurisdiction. Furthermore, users
should be aware of any applicable legislation within their jurisdiction.
The term ‘appropriate authority’ is used in this case study. It is an NCC defined term
meaning the relevant authority with the statutory responsibility to determine the
particular matter. In general, this will be a building surveyor in respect to the Building
Code of Australia (BCA), or may be a government entity with authority.
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Case study: Accessible entrance
Introduction
In this accessibility case study we step through the Performance Solution process for
a design looking to provide an accessible entrance for a retail fitout.
For any parts of the design using a Performance Solution, the Performance Solution
process must be used.
The Design
The client has engaged an architect to develop the designs and documentation for a
retail fitout to an existing Class 6 building, including provision of an alternative
accessible entrance. Early in the design, it is proposed to use a combination of
Performance and Deemed-to-Satisfy (DTS) Solutions for the design of the accessible
entrance.
The case study design is representative of a ground floor retail fitout, see Figure 1.
Figure 1 Existing retail unit with no accessible entrance.
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The Process
Step 1 Prepare a performance-based design brief
The purpose of the performance-based design brief (PBDB) is to record the
fundamental activities and outcomes of the process, as agreed by stakeholders.
Typically the brief process is initiated by the designer. Figure 2 illustrates each
component in developing the brief.
Figure 2 Process of developing a performance-based design brief
Scope
• Client brief • Technical requirements • Regulatory requirements
Communicate with key
stakeholders
• Identification • Engage • Consult • Collaborate • Manage process
Document relevant data
Stakeholders sign off on
agreed brief
• Subject building • Scope and basis of proposal • Applicable Performance Requirements • Agreed acceptance criteria • Applicable assessment processes • Scope of evidence • Required documentation and report format
• Summary of proposal • Descriptions and explanation of proposed solution • Nominated applicable Performance Requirement(s) • Agreed acceptance criteria • Required scope of supporting evidence • Format and content of final report • Acknowledgement of participants
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Case study: Accessible entrance
Scope
Preparation of a PBDB starts with determining the scope for the building or parts of
building that will be subject to a Performance Solution.
In this case study, the project comprises a retail fitout (no change of use) to a 60 m2
ground floor tenancy within an existing building. The principal (and only) entrance
has a stepped access from the footpath. An alternative accessible entrance is
proposed as part of the works. The design needs to address the constraints of the
building and comply with the relevant NCC requirements. A ramp based on a DTS
Solution would impact significantly on the internal layout of this small retail unit, as it
would require an intermediate landing. As an alternative, the designer has suggested
a single length of ramp could be achieved if the ramp started close to the allotment
boundary and ran alongside an existing masonry partition. This would impact the set
back of 900 mm (in the DTS Provisions) as well providing a landing within the
allotment boundary (see Figure 3). The focus of the solution is to provide an
accessible entrance for the retail building using a combination of Performance and
DTS Solutions.
Figure 3 and Figure 4 demonstrate the options to address the 285 mm level
difference, requiring a 3990 mm long ramp at 1:14 grade. Figure 3 illustrates a
possible option satisfying the DTS Provisions, whereas Figure 4 provides a
Performance Solutions option that minimises impact on the retail area while still
providing ramp accessibility to the retail tenancy.
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Case study: Accessible entrance
Figure 3 DTS Solution - recessed ramp requiring intermediate landing
Figure 4 Proposed Performance Solution - ramp utilising footpath as landing
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Case study: Accessible entrance
Stakeholders
Consultation and active engagement with stakeholders is a fundamental component
in the process of formulating an appropriate scope of work. Identification and
engagement of the relevant stakeholders will often happen in conjunction with
scoping the proposed solution including advice on appropriate acceptance criteria,
NCC Assessment Methods, potential risks and mitigation strategies.
Table 1 shows the initial stakeholders and their respective roles. The stakeholders
are engaged to provide advice on the technical feasibility of developing NCC
compliant designs given the constraints of the existing building, and in line with its
proposed occupancy and use characteristics. The stakeholder group agreed by email
that the architect will manage the development of the design including the PBDB.
Table 1 Initial stakeholders and their roles
Stakeholder Role
Client (tenant) Retail lease holder
Property owner Authorises lessee works
Architect Lead design consultant
Appropriate authority Statutory assessment role (building surveyor)
Access consultant Advise on universal and accessible design
Alert:
It is crucial that the appropriate authority is not asked to provide design advice. It is
a conflict of interest for those with regulatory responsibility to assess aspects of a
design that they have contributed to the development of.
Document relevant data
The inputs and negotiations of stakeholders should document relevant data. This is
where all the agreements made though the briefing process are set out, in addition to
any known limitations or assumptions that underpin the agreements made. The
specific acceptance criteria including compliance benchmarks that were agreed and
the methods of demonstrating conformity with them must be clearly documented.
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Documenting relevant data is a process that brings together information on:
Subject building (described earlier in “The Scope” section)
Scope and basis of proposal
Applicable Performance Requirements
Agreed acceptance criteria
Applicable assessment processes
Scope of evidence
Required documentation and report format.
Note this is usually not a linear process, with concurrent documentation determined
from activities, decisions, reviews and updates to designs. Further, the
documentation identified and outlined in the PBDB will form the basis for the final
Performance Solution report.
Scope and basis of proposal
Following an initial review, the access consultant collaborates with the architect and
determines that it is technically possible to form an alternative accessible entrance,
including a ramp, and that it requires to be addressed through a combination of DTS
and Performance Solutions. In particular, aspects of design requiring a Performance
Solution are:
1. Landing of adequate size cannot be provided at base of ramp within the
allotment boundary.
2. Ramp cannot be set back at a minimum of 900 mm preventing:
(a) Placement of tactile ground surface indicators (TGSIs); and
(b) Extension of handrails.
The occupancy and use characteristics of the proposed retail unit are agreed to be
persons reflective of the general population, including people with disabilities, and
conscious and active (not sleeping or otherwise infirm) participants in a retail setting.
Determining applicable Performance Requirements
In this case study, the proposed approach is to demonstrate compliance with a
combination of DTS and Performance Solutions. A2.4(3) requires that the relevant
DTS Provisions are identified together with their relevant Performance Requirement
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and any other affected Performance Requirements. Table 2 maps these NCC
requirements to the identified technical issues.
Table 2 Mapping NCC requirements to identified technical issues
Technical issue Applicable DTS Provision/s
Relevant Performance Requirement1
Other relevant Performance Requirements
1. Landing of sufficient size cannot be provided at base of ramp within the allotment boundary
2(a) Ramp cannot be set back preventing placement of TGSIs
D3.3(a)(i)
Does not comply with AS 1428.1 Clause 10
D3.3(a)(i)
Does not comply with AS 1428.1 Clause 10 and
D3.8(a)(iv) and (b)
Does not comply with AS 1428.4.1 Clauses 1 or 2
DP1 Access for people with a disability
DP1 Access for people with a disability
DP2 Safe movement to and within a building
NA
NA
2(b) Ramp cannot be set back preventing extension of handrails
D3.3(a)(i)
Not comply with AS 1428.1 Clause 10
DP1 Access for people with a disability
DP2 Safe movement to and within a building
NA
Note:
1. For applicable DTS Provision/s
The next step is to determine acceptance criteria for the Performance Solution.
Acceptance criteria
Acceptance criteria are the cornerstone of developing a Performance Solution. They
need to be established to ensure the relevant Performance Requirements are met for
the particular project given the occupancy and use characteristics of the building.
Establishing the acceptance criteria requires teasing apart the technical issue, the
intent or purpose of the relevant Performance Requirements and DTS Solutions, and
how the proposed design impacts on the occupancy and safe use of the building.
This is necessary to pinpoint the technical matters to be addressed. Once the
specific technical matters have been identified, the design response can be
considered, including relevant acceptance criteria.
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Case study: Accessible entrance
This process started with the mapping of the NCC requirements in Table 2, but
needs to be examined in more detail. In this case study, the two relevant
Performance Requirements are:
DP1 Access for people with a disability
DP2 Safe movement to and within a building
In the context of this case study, DP1 has the qualifier ‘to the degree necessary’.
However, the proposed new entrance will be the only accessible route into the
building. This means the proposed solution needs to ensure an appropriate level of
accessibility. DP2 Safe movement to and within a building, has the qualifier ‘must’.
Features related to DP2 are a ‘must’ and evidence and justifications to support a
proposed solution need to be robust.
DP1 Access for people with a disability
Access must be provided, to the degree necessary, to enable—
(a) people to—
(i) approach the building from the road boundary and from any accessible
carparking spaces associated with the building; and
(ii) approach the building from any accessible associated building; and
(iii) access work and public spaces, accommodation and facilities for
personal hygiene; and
(b) identification of accessways at appropriate locations which are easy to find.
Limitation
DP1 does not apply to a Class 4 part of a building.
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DP2 Safe movement to and within a building
So that people can move safely to and within a building, it must have—
(a) walking surfaces with safe gradients; and
(b) any doors installed to avoid the risk of occupants—
(i) having their egress impeded; or
(ii) being trapped in the building; and
(c) any stairways and ramps with—
(i) slip-resistant walking surfaces on—
(A) ramps; and
(B) stairway treads or near the edge of the nosing; and
(ii) suitable handrails where necessary to assist and provide stability to people
using the stairway or ramp; and
(iii) suitable landings to avoid undue fatigue; and
(iv) landings where a door opens from or onto the stairway or ramp so that the
door does not create an obstruction; and
(v) in the case of a stairway, suitable safe passage in relation to the nature,
volume and frequency of likely usage.
Holistically, these Performance Requirements may be considered to require:
a continuous accessible path of travel
continuous movement
safe movement
provision of information
protection from hazards.
For the purposes of this case study, the approach used to derive the acceptance
criteria is a ‘what, where, who, how, why, and when’ approach. By asking what,
where, who, how, why, and when, the detailed technical matters to be addressed in
the Performance Solution can be teased out, as well as the context for the solution.
Issue 1 - Ramp landing
What is affected and where?
The landing at the base of the ramp serving the accessible entrance. This is
located on the ground floor, as part of the continuous accessible path of travel
to the accessible entrance. This is the only accessible path of travel to the retail
unit.
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How and why is the building, part of building, facility, component,
material, etc. affected?
The space for a landing at the base of the ramp is inadequate and cannot be
provided within the allotment boundary.
Purpose of landing is to provide a safe transition to/from a ramped surface. The
lack of an adequate landing may be detrimental to safe use of the ramp.
Who is affected, how and why?
The occupancy and use of the building is identified as persons reflective of the
general population, including people with disabilities.
The ramp may be used by all building users and is of particular importance for
people using wheeled devices, such as prams, people with a mobility
impairment including users of wheelchairs, walking aids etc., as well as people
with a vision impairment.
These building users are potentially affected because the landing provides a
safe transition to/from a ramped surface.
For a person using a mobility aid, or wheeled device, the landing provides a
space to align correctly with the ramp to make a safe ascent/descent. For a
person with a visual impairment, the landing provides an important transition
point to orientate and address the change in level, which might otherwise be a
hazard.
When is the specific issue important?
At all times the building is in use.
Issue 2 - Ramp cannot be set back at a minimum of 900 mm, or sufficiently, to
ground floor, alternative accessible entrance
What is affected and where?
There is inadequate setback for the ramp from the allotment boundary affecting
(a) the placement of TGSIs, and (b) the provision of handrail extensions.
The ramp serves the accessible entrance to the ground floor retail unit, as part
of the continuous accessible path of travel. This is the only accessible path of
travel to the retail unit.
How and why is the building, part of building, facility, component,
material, etc. affected?
(a) TGSI placement – is required at the top and bottom of a ramp. The lack of
a setback means that TGSIs cannot be provided to the bottom landing.
(b) Extension of handrails is required beyond the top and bottom of a ramp
surface. The lack of a setback and adequate space means that handrail
extensions cannot be provided to the bottom landing.
Who is affected, how and why?
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(a) The purpose of TGSIs is to provide information and warn users of
hazards, especially people with a vision impairment. TGSIs also provide
predictability in the environment which improves safety and allows for
continuous movement.
(b) Handrails provide all users with stability to allow for safe use of a ramp.
This includes people with mobility, ambulant and visual impairments.
Handrails provide important information for people with a vision
impairment to allow continuous, predictable and safe use of a ramp.
When is the specific issue important?
At all times the building is in use.
Having worked through the detail of the issues to be resolved and considering the
context that they occur, the design response and acceptance criteria can be
developed. These are summarised in Table 3a and Table 3b. Limitations and
assumptions are also stated here.
Table 3a Summary of technical matters, the proposed design response and acceptance criteria
for Issue 1 - Ramp landing
Matters to be
addressed
Design response Acceptance criteria
Provision of alternative
design features for
safe use of ramp, to
consider needs of
people with mobility
and vision impairments
– landing space and
entrance
Consider the use of the
footpath as providing
adequate space to provide
a landing.
Assess available footpath
space, crossfalls and
transitions, against the
minimum space in the DTS
Provisions.
Consider safe egress where
no landing.
To achieve circulation
space for a 90% wheelchair
footprint.
To achieve a crossfall
gradient no steeper than
1:40 (1:33 if bitumen).
To achieve a transition of
not more than ±5 mm, for
bevelled edges.
Provide sensor activated
powered entrance doors for
safe egress
Provision of alternative
design features for
safe use of ramp, to
consider needs of
people with mobility
and vision impairments
– hazard recognition
To improve hazard
recognition for people with
a vision impairment (and
others), provide ramped
surface with contrasting
colour to surrounding
walls/surfaces and landing
area outside allotment
boundary.
Minimum luminance
contrast of 30% to be
achieved and verified upon
completion of construction
works.
Further input required from
lighting consultant.
Acceptance criteria to be
agreed.
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Matters to be
addressed
Design response Acceptance criteria
Review lighting design to
ensure minimum levels of
illumination and to minimise
impact of glare and
shadowing.
Limitations/Assumptions
Footpath outside control of tenant.
Footpath finish may change affecting luminance contrast.
Footpath may fall into disrepair affecting transition across surfaces.
Relies on expert judgment from access consultant that the proposed design
responses are adequate to meet the Performance Requirements.
Further input required from lighting consultant.
Table 3b Summary of technical matters, the proposed design response and acceptance criteria
for Issue 2: Ramp setback
Matters to be
addressed
Design response Acceptance criteria
Provision of alternative
design features for safe
use of ramp, to consider
needs of people with
mobility and vision
impairments.
Provide design features for safe
use of ramp:
Hazard recognition for people
with a vision impairment (and
others), to be improved by
providing ramped surface with
contrasting colour to
surrounding walls/surfaces
and landing area outside
allotment boundary (see
above).
Review lighting design to
ensure minimum levels of
illumination and to minimise
impact of glare and
shadowing.
TGSIs within the retail unit are
to be provided to warn of the
ramp hazard, even though
there will not be
corresponding TGSIs at street
end of the ramp.
Minimum luminance
contrast of 30% to be
achieved and verified
upon completion of
construction works.
Further input required
from lighting consultant.
Hazard TGSIs to be
provided to AS 1428.4.1.
A dome button is to be
incorporated the end of
each handrail
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Matters to be
addressed
Design response Acceptance criteria
Warn users of the end of the
handrail where stopped short.
Limitations/Assumptions
Relies on expert judgment from access consultant that the proposed design
responses are adequate to meet the Performance Requirements.
Further input from lighting consultant.
As we can see, further input is required from a lighting consultant to advise on
appropriate lighting design and light levels. The lighting consultant would be an
additional stakeholder. Further advice from the lighting consultant added additional
acceptance criteria of minimum illumination of 100 lux and fittings specified with
placement to minimise glare and shadowing.
Fundamental to the success of the Performance Solution process is that there is
general agreement amongst the stakeholders on the acceptance criteria for the
proposal. It is essential to have the agreement of the appropriate authority for the
project. Without their agreement at this stage the completed design documentation,
including the performance proposal, may not be accepted.
Assessment processes
In this case study, the appropriate authority notes that A2.2 and A2.3 in the NCC sets
out Assessment Methods that can be used for Performance and DTS Solutions
(respectively). It was agreed by the stakeholders that the following NCC Assessment
Methods are likely relevant:
Evidence of suitability
Expert Judgement
Comparison with the DTS Provisions.
The appropriate authority will need to be satisfied that relevant acceptance criteria
are established and that the NCC Assessment Methods and other information to be
provided with the design documents, will be adequate to determine NCC compliance
is achieved.
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Scope of evidence
The evidence required to support the components of a Performance Solution is determined by
determined by the NCC Assessment Methods. The PBDB notes that certain stakeholders are
stakeholders are responsible for providing the evidence (see Table 4a and
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Table 4b).
Table 4a Summary of technical issue, NCC Assessment Method/s, evidence and person/entity
responsible to provide evidence for Issue 1 – Ramp landing
Summary design response and acceptance criteria
NCC Assessment Method
Evidence (Provided by)
Use footpath as landing: Comparison Accurate drawings showing the
To achieve circulation space
for a 90% wheelchair
with DTS Provisions
proposed building works and the arrangement of the footpath, ramp and entrance (Design practitioner)
footprint. Report from an appropriately qualified
To achieve a crossfall person on efficacy of design responses
gradient no steeper than (Access consultant)
1:40 (1:33 if bitumen).
To achieve a transition of not
more than ±5 mm, for
bevelled edges.
Provide sensor activated
powered entrance doors for
safe egress.
Safe use of ramp: Expert Accurate drawings and specifications
Minimum luminance contrast
of 30% to be achieved
judgement
Evidence of
detailing the proposed finishes (Design practitioner)
between ramp surface and
surrounding walls, landing
and footpath; to be verified
upon completion of
construction works.
suitability
Comparison with DTS Provisions
Report from appropriately qualified person on efficacy of design responses (Access consultant)
Report from NATA accredited laboratory on LRVs for proposed materials (NATA laboratory)
Minimum 100 lux on ramp.
Light fittings and placement Report confirming onsite testing results of luminance contrast upon completion
to minimise glare and of works (Appropriately qualified person
shadowing. for onsite testing)
Lighting design, specification and onsite testing (Lighting consultant)
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Table 4b Summary of technical issue, NCC Assessment Methods, evidence and person/entity
responsible to provide evidence for Issue 2 – Ramp setback, TGSI placement and handrail
extensions
Summary design response and acceptance criteria
NCC Assessment Method
Evidence (Provided by)
Safe use of ramp:
Minimum luminance contrast
of 30% to be achieved
between ramp surface and
surrounding walls, landing
and footpath; to be verified
upon completion of
construction works (as
above).
Minimum 100 lux on ramp.
Light fittings and placement
to minimise glare and
shadowing.
Hazard TGSIs to be provided
to top ramp landing to
AS 1428.4.1.
Provide dome button to
specification in AS 1428.4.1,
where handrails stopped
short.
Expert judgement
Evidence of suitability
Comparison with DTS Provisions
Accurate drawings and specifications detailing the proposed finishes (Design practitioner)
Report from appropriately qualified person on efficacy of design responses (Access consultant)
Lighting design, specification and onsite testing (Lighting specialist)
Step 2 Carry out analysis
Analysis, assessment and verification are different activities within the Performance
Solution process. It is important to ensure that adequate analysis has been carried
out prior to making an assessment and prior to verifying NCC compliance.
In this case study, the following analyses are undertaken:
Quantitative analysis to measure the illumination and luminance contrast.
Qualitative analysis to confirm the equivalence, or better, of proposed designs
to adequately address the NCC Performance Requirements.
Comparative approach with other DTS Solutions, including with NCC
referenced standards, for measurement of landing spaces, transitions and
crossfalls and for handrail design, including use of a dome button.
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Alert:
Ultimately, agreed analytical processes may need to be reviewed if initial outcomes
do not meet the agreed acceptance criteria.
If for this case study, the review of the footpath revealed that it has crossfalls steeper
than 1:40, the stakeholders would need to review the information and consider
whether the proposed design is still acceptable. As this is the only accessible
entrance, failure to not meet this acceptance criteria may require a different design
solution.
Similarly, if the required luminance contrast cannot be achieved with the proposed
finishes, different finishes will need to be specified.
Step 3 Evaluate results
During the process of analysis, design scenarios may have been considered and
analysed. The evidence and design documents need to verify that the chosen design
approach satisfies the agreed acceptance criteria, and in turn, meets the NCC
Performance Requirements. The evaluation of results is therefore a critical
component of the Performance Solution process.
Evaluating each of the acceptance criteria in this way assists verifying compliance. It
also can assist the design team if there are any ‘failures’, as these can be put into
context more easily. In this case study, not achieving an acceptable cross fall for the
ramp landing would likely require a significant redesign of the ramp. Whereas, not
achieving the required luminance contrast would only require an adjustment to the
choice of finishes.
Note, that the evaluation may also not be a linear process, and evaluation of the
analysis and results may occur iteratively throughout the process.
Step 4 Prepare a final report
The final report is sometimes referred to as a Performance Solution report. Its prime
purpose is to provide the means of verifying compliance with the NCC Performance
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Requirements. The appropriate authority will use the Performance Solution report for
compliance assessment purposes.
The final report also shows how the construction conforms with the approved design
and relevant regulatory, technical, and client specified requirements.
A summary of the Performance Solutions are outlined in Table 5a and Table 5b. Note
the final report format is really just an extension of the PBDB document.
The Performance Solution process may have considered a range of non-NCC
matters, but the final report only needs to demonstrate that compliance with the NCC
Performance Requirements outlined in the brief has been achieved. The content of a
typical final report must comply with A2.2(4)(d) and for this case study may include:
An overview of the brief, including:
Scope of the project
Stakeholders
Applicable NCC Performance Requirements and DTS Provisions
Acceptance criteria agreed to by stakeholders
Approaches to methods of analysis
NCC Assessment Method/s used
Any assumptions that were made
Limitations
Overview and outline of the analysis, modelling and/or testing carried out
Method of analysis used
The results obtained and relevance to the brief
Evaluation of results including:
Comparison of results with acceptance criteria
Any expert judgement applied and its justification
Conclusion
Specifications of the final design that are deemed to be acceptable
Confirmation that the NCC Performance Requirements/s were met
All limitations to the design and any conditions of use.
The conclusion of the final report must include key design decisions, assumptions
and limitations that may affect future decisions for the building.
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Table 5a Summary of Performance Solution for Issue 1 – Ramp landing not within allotment boundary
NCC Requirements (Applicable DTS, PR, Other PRs)
Summary design response and acceptance criteria
NCC Assessment Method
Evidence (Provided by)
DTS
D3.3 (a)(i) Does not comply with AS 1428.1 Clause 10
Performance Requirement
DP1 Access for people with a disability
Other PRs
NA
Use footpath as landing:
To achieve circulation space for a
90% wheelchair footprint.
To achieve a crossfall gradient no
steeper than 1:40 (1:33 if bitumen).
To achieve a transition of not more
than ±5 mm, for bevelled edges.
Provide sensor activated powered
entrance doors for safe egress.
Safe use of ramp:
Minimum luminance contrast of 30%
to be achieved between ramp surface
and surrounding walls, landing and
footpath; to be verified upon
completion of construction works.
Minimum 100 lux on ramp. Light
fittings and placement to minimise
glare and shadowing.
Comparison with DTS Provisions
Expert judgement
Evidence of suitability
Accurate drawings showing the proposed building works and the arrangement of the footpath, ramp and entrance and the proposed finishes (Design practitioner)
Report from appropriately qualified person on efficacy of design responses (Access consultant)
Report from NATA accredited laboratory on LRVs for proposed materials (NATA laboratory)
Report confirming onsite testing results of luminance contrast (Appropriately qualified person for onsite testing)
Lighting design, specification and onsite testing (Lighting consultant)
Note:
PR = Performance Requirement
abcb.gov.au Page 22
Case study: Accessible entrance
Table 5b Summary of Performance Solution for Issue 2 – Ramp setback, TGSI placement and handrail extensions
NCC Requirements (Applicable DTS, PR, Other PRs)
Summary design response and acceptance criteria
NCC Assessment Methods
Evidence (Provided by)
Issue 2a TGSIs
DTS
D3.3 (a)(i) Does not comply with AS 1428.1 Clause 10
D3.8(a)(iv) and (b) Does not comply with AS 1428.4.1 Clauses 1 or 2
Performance Requirement(s)
DP1 Access for people with a disability DP2 Safe movement to and within a building
Other PRs NA
Safe use of ramp
Minimum luminance contrast of 30%
to be achieved between ramp
surface and surrounding walls,
landing and footpath; to be verified
upon completion of construction
works. (As above).
Minimum 100 lux on ramp. Fittings
and placement to minimise glare
and shadowing.
Hazard TGSIs to be provided to top
ramp landing to AS 1428.4.1.
Expert judgement
Evidence of suitability
Comparison with DTS Provisions
Accurate drawings and specifications detailing the proposed finishes (Design practitioner)
Report from appropriately qualified person on efficacy of design responses (Access consultant)
Lighting design, specification and onsite testing (Lighting specialist)
Issue 2b Handrail extensions Safe use of ramp: Comparison with DTS Accurate drawings and
DTS
D3.3 (a)(i) Does not comply with AS1428.1 Clause 10
Provide dome button to specification
in AS 1428.4.1, where handrails
stopped short.
Provisions specifications detailing the proposed handrail (Design practitioner)
Report from appropriately
Performance Requirement(s)
DP1 Access for people with a disability DP2 Safe movement to and within a building
qualified person on efficacy of design responses (Access consultant)
Other PRs NA
Note:
PR = Performance Requirement
abcb.gov.au Page 23
Case study: Accessible entrance
References
ABCB (Australian Building Codes Board) (2019) National Construction Code (NCC)
Amendment 1 Complete Series, ABCB, accessed Jan 2021.
ABCB (Australian Building Codes Board) (2021) Performance Solution process
Handbook, ABCB, accessed April 2021.
Standards Australia, AS 1428.1 Design for access and mobility, Part 1: General
requirements for access – New building work. Standards Australia, accessed Jan
2021.
Standards Australia, AS 1428.4.1 Design for access and mobility, Part 4.1: Means to
assist the orientation of people with vision impairment – Tactile Ground Surface
Indicators. Standards Australia, accessed Jan 2021.
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